Electron tube mount comprising a plurality of electrode cages



Apnl 22, 1969 M. R. BENSON ET AL 3,440,472

ELECTRON TUBE MOUNT COMPRISING A PLURALITY OF ELECTRODE CAGES I Filed Aug. 18, 1966 INVE TOR5 E I MART/N 7?. ENSON, l 9- BY A/vso/v c. .Bmwzu,Je. fi/rQ/{jZn w ATTORNEY United States Patent US. Cl. 313-260 3 Claims ABSCT OF THE DISCLOSURE An electron tube mount having plural electron cages wherein each of the cages is formed as a separate and distinct entity including top and bottom micas and the mount is formed b tying the cages together by a single,

common mica.

This invention pertains to electron tube mounts and more particularly to such mounts that comprise two or more electrode cages, each functioning as individual tubes.

It has long been recognized that many advantages accrue to the utilization of plural tube structures. Not the least of these are the savings which result from the lesser amounts of materials utilized and the cost savings which result from the use of automatic assembly machines which can assemble a plural cage mount in almost the same time as a single cage mount. Previous plural cage mounts have all suffered from one or a combination of several glaring faults. Among these faults are the following: it was necessary to redesign either one or more of the supporting micas; or one or more of the electrode cages or individual electrodes had to be redesigned so that they might be assembled together. Occasionally individual electrode cages were assembled with special micas on either the top or bottom thereof and then these micas were attached to one another by various means such as stapling or pegging. This greatly increased the cost and the amount of handling necessary for the fabrication of these tubes. Still other approaches have meant redesigning entire tube structures or individual electrodes. Still others attempted merely to insert all of the required tube electrodes into single micas; however, since the mica supports used in tubes are relatively fragile laminated structures they become greatly weakened and extremely difficult to handle when provided with vast numbers of electrode receiving apertures. They are also more subject to delamination as the number of electrode receiving apertures increases.

It is, therefore, an object of this invention to enhance electron tube mounts comprised of a plurality of electrode cages.

Another object of the invention is the provision of an electron tube mount that obviates the above-cited disadvantages.

It is another object of the invention to reduce the cost of such electron tube mounts.

It is yet another object of the invention to provide an electron tube mount having a plurality of electrode cages that are of conventional design with no required changes therein.

It is another object of the invention to provide an improved electron tube mount with plural electrode cages that is comprised of relatively simple, completely selfsupporting, sub-assemblies.

These objects are accomplished in one aspect of the invention by the provision of an electron tube mount assembly having a plurality of electrode cages each comprised of at least a cathode electrode and an anode electrode. These electrodes are spaced apart in a manner well known to the art and their spacing is maintained by virtue of the electrodes being sandwiched between a pair of supporting micas having apertures therein to receive the extremities of the electrodes. These extremities of the electrodes usually project a given distance beyond the outer limits of the micas so that various electrical connections may be made thereto and to insure precise alignment of the electrodes. The projecting extremities of at least the outermost electrode of each cage, that is, the anode, are usually deformed in some suitable manner such as by bending over or by twisting and thus serve to hold the sandwich together. In the instant invention an elongated mica is superposed over the plurality of electrode cages and it is provided with apertures to receive the extremities of at least one of the electrodes from each of the plurality of cages. These extremities are then deformed and there is provided an electron mount structure that is rigid, simple to fabricate, and relatively inexpensive. Further, it has required the design and incorporation therein of only one new element, that is, the superposed mica. Since each of the electrode cages was a completely assembled unit, no changes were necessary in them to accommodate their use in a plural cage structure.

For a better understanding of the present invention, to gether with other and further objects, advantages, and capabilities thereof, reference is made to the following disclosure and appended claims in connection with the accompanying drawings in which:

FIG. 1 is an exploded elevational view of a plural cage electron tube mount illustrating an embodiment of the invention; and

FIG. 2 is a plan view of the mount of FIG. 1.

Referring now to the drawings with greater particularity, in FIG. 1 there is shown an electron tube 10, with parts of the glass envelope 12 being omitted for purposes of clarity and simplicity, having a plural cage mount structure 14. In this instance the mount structure 14 comprises two independent electrode cages 16 and 18.

"Electrode cage 16 is comprised of a cathode 20, grids 22 and 24 and an anode 26. These electrodes are maintained in their proper, spaced apart operating positions by upper and lower micas, 28 and 30 respectively, which sandwich the electrodes therebetween. The extremities of the cathode and grid electrodes, designated generally as 32, as well as tabs or cars 34 which are formed on the anode project with a snug fit through corresponding apertures in the micas to insure maintained alignment and to allow electrical connections to be made between the various electrodes and the stern leads 36 which project inside the tube.

Likewise, electrode cage 18 is comprised of a cathode 38, grids 40, 42 and an anode 46. Micas 48 and 50 complete the sandwich and the extremities of the cathode and grids, designated generally as 52, and the tabs 54 of the anode project therethrough as discussed above.

It is to be noted that while the two electrode cages illustrated here are similar, i.e., both tetrodes, it is by way of example only and any combination of types such as pentodes and triodes or diodes may be utilized with this invention.

Each of the cages 16 and 18 represent, however, independent tubes of standard form and are identical to the cages that would be employed when a single cage mount is constructed.

The plural cage mount is tied together by a superposed mica 56 which is formed to provide attaching means equal in number to the number of electrode cages to be in corporated into the final tube. The two cages in the embodiment discussed herein, it is to be noted, are by way of example only and more than two cage mounts are contemplated by this invention. Specifically, superposed mica 56 is of a size sufiicient to encompass the two upper micas 28 and 48 of cages 16 and 18. Large apertures 58 and 60 are provided in mica 56 as are anode tab receiving apertures 62. The large apertures 58 and 60 surround, without touching, extremities 32 and S2 of the electrodes. When assembled, anode tabs 34 and 54 project through anode tab receiving apertures 62 and are bent over to form a substantial angle, approximately 90, with the anode wall, thus forming a compact and rugged plural cage mount. The use of the large extremity surrounding apertures results in considerable cost savings over mica types wherein individual apertures are provided for the electrodes since considerable accuracy is required in the placement of these apertures.

Further, the one large aperture per cage does not result in the delamination that might occur if individual electrode apertures were formed.

Utilization of this invention which allows the use of the conventional or standard cages results in still further savings since these cages are manufactured on automatic assembly equipment that is expensive to change over. By not requiring new electrodes considerable design time is saved with its resultant cost savings.

This invention thus provides a plural cage mount that utilizes conventional cage structures, does not require mica stapling or pegging, and is more rugged and easier to manufacture than those used heretofore.

While there has been shown and described what is at present the preferred embodiment of the invention, it will be obvious to those skilled in the art that various changes and modifications may be made therein without departing from the scope of the invention as defined by the appended claims.

What is claimed is:

1. In an electron tube mount assembly a plurality of electrode cages each comprising at least a cathode electrode and an anode electrode, each of said plurality of cages being sandwiched between individual upper and lower micas having apertures therein to receive the extremities of said electrodes which extremities project therefrom, and a superposed mica extending across said upper micas of said plurality of electrode cages and provided with apertures to receive said extremities of at least one of said electrodes from each of said plurality of electrode cages.

2. The device of claim 1 wherein said electrode cages comprised a cathode, an anode, and one or more grid electrodes disposed therebetween, and said superposed mica is provided with a number of large apertures, said number being equal to the number of electron cages and so positioned to surround Without engagement the projecting extremities of said cathode and grid electrodes and being further provided with anode tab engaging slots, at least one slot for each anode of each electrode cage.

3. The mount structure of claim 2 wherein said superposed mica is held in place by the anode extremities.

References Cited UNITED STATES PATENTS 2,802,132 8/1957 Magers 3l3-26l 2,836,746 5/1958 Wolke et al. 3l326l X 3,193,716 7/1965 Beard 3l326l X JOHN W. HUCKERT, Primary Examiner.

R. F. POLISSACK, Assistant Examiner.

US. Cl. X.R. 

